Variable-speed pulley and v-belt transmission



NOV, 1951 G. o. TURNBULL 2,573,937

VARIABLE SPEED PULLEY AND V-BELT TRANSMISSION Filed Dec. 29, 1949 2 sHEETS-sHEET 1 INVENTOR. 62622, J 751272 ZZZ mqyw Nov. 6, 1951 G. o. TURNBULL 2,573,937

VARIABLE SPEED PULLEY AND V-BELT TRANSMISSION Filed Dec. 29, 1349 2 SHEETSSHEET 2 IN V EN TOR.

.1-.n1emb r m yor -"at Patented Nov. 6, 1951 UNITED S ATE "PATENT OFFICE vnRIABLE-sPEEn PULLEY AND V-BEIJT TRANSMISSION Glen "0. Turnbull, Rock Island, 111., assignor to "International Harvester Co'mpany, a corporation'of'New Jersey 7 ApplicaticnQDecember 29, 1949., SerialNo. 135,557

therebetween to ride "higher and lower within the pulleys and thereby change the transmitted speed from a driving to a .driven shaft. Various types of adjustable mechanisms have been .employed in order to accomplish the variable speed I transmissions. iTheiadjustment of one pulley re:

quired an equal adjustment .of the cooperative pulley in order to maintain a fixed spacing "between the pulle sections for a constant length V-belt. Further, in certain forms of adjustable pulleys there Ihasbeenprovidedyieldalole means particularly on one of the two pulleys so that an adjustment of one would automatically be com- ,pensated forby the yielding of the spring of the other. However, such .a construction tended to minimize the effectiveness of the transmission and an excessive load being carried thereby would cause the belt to slip with resultant unstablev power transmission and excessive uneven :belt wear.

'A principal object of this invention is to there- .30 tore provide tie means interconnecting the ad-" i'justable V-pll-leysin-sucha manner that one p111- ley is always moved an equal .amount tofthe adjustment of the other-of the cooperative'plilleys.

provision of- .means in :a variable speed v-ib elt transmission to provide means responsive to ,the adjustmentof one pulley toeffect-adjustment of the other :pulley .-in an equal amount. 4

:Another important object of this .invention is to zsupply means inpa variable speed V ebeltitransmission including :a tie mechanism through which a pair .of adjustable V- pulleys is-simul- ,taneously spaced anequal-distance andiprovid- 5 [half i6 is similarly 'beingrotated along with its iintegral parts, the sleeve 2i and the ring "22.

ing in the tie mechanism a-pre loaded resiliency land-a limited ,yielding means to automatically compensate for slight variations due to belt .-wear. 7

Another andstill ;further. important object of .50 -lthi5 invention :is to provide adjusting-mechanism .ifor I .a :pair :of cooperative. V- -pulleys including a I yieldable member and adjustable means forreg- -ulating -the ,;limits within which tlie wieldable Ihal'f sections it and n.

. --.3 vAn important :object of this :invention .is the" A'still further important object of this invention is to provide control mechanism for manually simultaneously shifting cooperative V-belt pulleys through an equal distance.

Other and further important objects of this invention will become apparent from the disclosures in the following specification and accompanying drawings. r

In the drawings:

Figure "l is a top plan view of the variable speed -V-belt transmission of this invention.

Figure 2 is a side elevational viewof the-device .as shown in Figure 1.

As shown in the drawings: The reference numeral it indicates generally a'supporting structure having a "driving shaft ll journale'd in one portion thereof and a driven shaft [2 lying parallel to and spaced "from the driven shaft H and similarly journaled within the supporting structure 10. A V-belt pulley I3 :is mounted over the driving shaft 11 and similarly a V-belt pulley It is mounted over the driven shaft 112. By means of a V-belt l5 drive is transmitted from the shaft H to the shaft l2,

"both or which are journally mounted in the supporting structure 10.

The V-b'elt pulley [3 is provided with Opposed The pulley half 16 is (provided with a hub portion !8 adapted to surround the shaft ll. .A key 19 joins 'the'hub l3 to theshait ll forconcurrentrotation of these parts. -Azballbearing 20 is disposed between -the supporting structure It] and the-end of thepulley half hub [B as well as encircling the shaft I I.

5 Thelbearingill thusis conducive to the rotation of theshaft and hub with respect to the stationary supporting structure lid.

[A sleevez-l is mounted on .thesha'ft H .andextends from a position adjacent the hub l8 to substantially the end of the shaft. A ring or washer-like member 22 surrounds the sleeve 2| ,adjacent its inner end and is welded 'theretolas shown at 23. The ring is fastened by means of rivets 24 to the pulley half [6. It is thus apparvent that as the shaft H is rotated the pulley pulley half I] by means .ofrrivets or the'like T21. "TheIpuIIey half ll isiformed with .an axially extending annular lip lzsconcentric with Ltheshait I I for the purpose of receiving a ball bearing 29. The outer race 30 is press-fitted within the sleeve-like lip 28 and abuts a shoulder 3| formed in the lip. The inner bearing race 32 surrounds the sleeve 25 but is spaced therefrom as shown by the'clearance '33. The pulley half I] along with the sleeve hub 25 and the ball bearing 23 is permitted axial movement along the splined sleeve 2| which superposes the shaft II and thus the spacing between the pulle halves l6 and I1 may be changed as desired. Slidable movement of the pulley half I! is accomplished by a shifting fork 34. The shifter fork 34 is pivoted at 35 on a bracket 36 forming a part of the supporting structure l0. As shown in Fig. 2 the bracket 36 stitutes a hinge for the shifter form 65. Fork fingers 66 in a generally U-shaped spacing are adapted to engage the outer side of the inner race 6| of the ball bearing 58 for the purpose of moving the pulley half 53 axially along the shaft l2 through the medium of the inter-engaging splines is generally yoke-shaped and has an openin 31 through which an operating arm 38 of the shifter form 34 extends. The fork 34 is provided with fingers 39 in the form of a U and arranged and constructed to engage the inner race 32 of the ball bearing 29 for axial movement of the bearing and the pulley half along the shaft (Similarly the pulley |4 includes a pulley half 40 Which has a sleeve-like hub 4| fastened by means of a key 42 to the shaft |2 to be driven. An elongated sleeve 43 is mounted on the shaft l2 in a manner similar to the sleeve 2|. An annular ring member 44 is welded to the sleeve 43 1 at 45 and forms' an outwardly extending flange for the sleeve 43. The ring member 44 is fastened to the pulley half 48 by means of rivets 46. Thus, as the pulley half 45 is rotated the structure including the sleeve 43, ring 44, and the shaft |2 will similarly rotate.

(A nut 41. threadedly engages the end 43 of the shaft |2 and through the medium of a washer 49 maintains the pulley structure on the confines of the shaft |2. The V-pulley l3 and its associated structure is also maintained on the shaft against endwise movement by means of a nut 50 upon threadedly engaging the end of the shaft The nut 58 maintains a washer 52 against the sleeve 2| thus holding the sleeve against axial movement off the end of the shaft 7 (The pulley |4 also includes a pulley half 53 adapted for sliding movement toward and away from the pulley half 40. The sleeve 43 is externally splined to slidably receive an internally splined sleeve 54. The sleeve 54 has an outwardly extending annular fiange 55 which is fastened by means of rivets 56 to the pulley half 53. Thus the pulley half 53 with its integral sleeve hub 54 may be moved along the splined sleeve 43 with respect to the pulley half and yet regardless of the position of the pulley half 53 the interengaging splines between the members 43 and 54 cause concurrent rotational drive of both pulley halves 40 and 53. This, of course, is similar to the construction in the pulley l3 wherein the pulley half IT is movable toward and away from the pulley half l6, maintaining concurrent drive of both pulley halves.

(The movable pulley half 53 is equipped with of shifter fork 65 is mounted. The shaft 64 con- 8| of the super-structure 88.

on the sleeve members 43 and 54. The shifter form 65 is provided with an arm 6'! for the purpose of eifectingarcuate swinging movement of the fork fingers 66.

The shaft 64 has fastened thereto a pair of upwardly extending spaced arm members 68 and 63. These arms carry a link member '38 at their upper end by means of a pin 1|. The link '50 is for. the purpose of causing a shifting of the fork members 34 and 85 and may be extended to some remote position.

A tie link mechanism 12 is provided between the shifter fork 34 and the shifter fork 55 and more specifically the arm members 13 and 61. It should be understood that as one pulley has its spacing narrowed the cooperating pulley has its effective belt spacing widened. The pulley halves l1 and 53 will be moved an equal distance as the operating link 'lfiris shifted. Inasmuch as the movable pulley half of, each of the pulleys l3 and M is located on the opposite side, the pulley-halves and 53 are moved in the same direction but act to oppositely open and close their respective pulleys. Therefore, a constant length V-belt |5 may be used without change'throughout the entire adjustment of the pulley drive.

The link mechanism i2 includes a first rod member 14 which is pivotally attached to the fork arm 81 at 15. 'An intermediate portion of the rod 14 is threaded as shown at 16 for receiving a nut 11. The link mechanism 12 further includes a second rod member 18 which is pivotally attached to the fork arm13 at 19. A superstructure having a sleeve portion 8| is fixedly carried on the rod 18 by means of a cross pin 82. This super-structure 80 includes a sleeve 83 axially aligned with the sleeve 8| and spaced therefrom. The sleeve 83 is arranged and constructed to slidably engage the end portion 84 of the first rod member 14. The sleeves 8| and 83 are joined by means of the laterally disposed supporting member 85. Thus the superstructure 88- includes the spaced apart sleeves 8| and 83 along with the entire member 85. The end of the sleeve 83 is equipped with an annular flange 85 for maintaining a coil spring 81 against a washer88 which abuts the nut 11 a spaced distance from the fiange 86. With this construction it will be seen that without other limiting means the first and second rod members 74 and '18 of the link mechanism 12 will be capable of telescoping the distance required to completely compress the coil spring 81.

In the present device it is not desired to have full unlimited telescoping of the rod members 14 and 18 and thus a bolt member 89 threadedly engages internal threads 98 in the sleeve portion The bolt head 9| may thus be positioned with more or less spacing as shown at 92 with respect to the end of the 7 rod 14. A lower nut 93 is carried on the bolt' 89 and is employed for the purpose of holding the bolt 89 in any desired adjusted position. The length of the space 92 determines the amount of yieldable telescoping between the first and second rods 14 and 18. If the bolt 89 were to be withdrawn from the threaded socket so that the head 3| abutted the end ofthe rod 14 there wouldbe no yieldabilityin the'link mechanism 59. Similarly, when the bolt 89 is screwed into the threaded socket 90 a greater space is created at 92 thus permitting the coil spring 81 to be compressed an amount equal to the length of the space 92.

The spring 81 is previously pre-loaded or in other words put under an initial compression so that there is always a constant tendency for the spring to separate the first and second rod members 14 and 18 to thus normally urge both of the slidable pulley halves l1 and 53toward their cooperative fixed pulley halves I6 and 40. This places a limited spring load on the V-belt I5. It should be understood that slight wear and variations in the V-belt will thus be compensated by this initial spring loading of the coil spring '81.

In operation, a user of the device of this invention may efiect change in speed transmission from the driving to the driven shaft by pulling or pushing on the control link 10. This directly changes the separation of the pulley halves l1 and 53 an equal amount with respect to their respective cooperative fixed pulley halves l6 and 40 so that the constant length V-belt 15 functions in all adjusted positions of the transmission pulleys l3 and 14. During imparting of the drive from the drive shaft II to the driven shaft l2 slight variations caused by belt wear or the like are compensated for by the preloading of the spring 81 which is positioned intermediate the first and second rod members 14 and 18 respectively. The spring 81 is arranged so that it will urge the pulley halves of both pulleys together and it is similarly arranged and constructed so that when the pulley halves tend to separate, such separation occurs only against the action of the spring 81 until such time as the space 92 is entirely eliminated causing the link mechanism 12 to become rigid throughout its length. It will thus be seen that the pulley transmission system of this invention is relatively stable and yet has adjustable limiting yieldable characteristics which are vitally necessary to effective and continued operation of such a device.

Numerous details of construction may be varied throughout a wide range without departing from the principles disclosed herein, and I therefore do not propose limiting the patent granted hereon otherwise than as necessitated by the appended claims.

What is claimed is:

l. A variable speed pulley and V-belt transmission comprising a supporting structure, a driving shaft'journaled on said supporting structure, a driven shaft parallel to and journaled on said supporting structure, a first adjustable V- pulley mounted on said driving shaft, a second adjustable V-pulley mounted on said driven shaft and in alignment with said first adjustable V-pulley, said first adjustable V-pulley having a half thereof fixed to said drive shaft and the other half thereof slidable on said drive shaft toward and away from said fixed half, said second adjustable V-pulley having a half thereof fixed to said driven shaft in alignment with the slidable half of the first adjustable V-pulley and the other half thereof slidable on said driven shaft in alignment with the fixed half of the first adjustable V-pulley, a first fork means pivotally mounted on'said supporting structure adjacent the slidable half of the first adjustable V-pulley, a second fork means pivotally mounted on said supporting structure adjacent the slidable half of the second adjustable V-pulley, a V-belt joining said first and second adjustable V-pulleys,

tie rod means having limited yielding means incorporated therein joining the first and second fork means, whereby a shifting of said tie rod means causes an equal shifting of said slidable pulley halves, said tie rod means including a first 7 rod member, a second rod member spaced from and in axial alignment with the first rod member, a collar on the first of said rods, a superstructure fastened to the second of said rods and having a sleeve portion slidably journaled on the first of said rods, spring means interposed between said collar and said sleeve, and an adjustable screw means provided on the end of the second of said rods whereby the space between the ends of the. first and second rods may be adjusted.

2. A device as set forth in claim 1 in which means is provided for manually shifting said tie rod means.

GLEN O. TURNBULL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 350,053 Guttinger Sept. 28, 1886 2,336,022 Everett Dec. 7, 1943 FOREIGN PATENTS Number Country Date 136,293 Germany Nov. 24, 1902 11,307 Great Britain 1904 

